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41.
观察预注高渗氯化钠羟乙基淀粉40注射液对肝肿瘤合并高血压患者硬膜外复合全身麻醉诱导期的脑保护作用。选择50例患有高血压ASA分级Ⅱ级~Ⅲ级肝肿瘤手术患者,随机分为高渗氯化钠羟乙基淀粉40注射液(H)组和复方氯化钠(复方乳酸林格液R)组,每组25例。于输注前(T0)、输注完毕即刻(T1)、气管插管后即刻(T2)、气管插管后5min(T3)、气管插管后15min(T4)、气管插管后30min(T5)抽取静脉血离心后检测血清中S100B、IL-6、TNF-a的浓度。与T0点相比,H组,T5点S100B轻度降低但无统计学差异(P0.05),IL-6、TNF-a无明显变化(P0.05);R组在T5点S100B明显上升(P0.01);IL-6、TNF-a明显上升(P0.05或P0.01)。与R组相比,H组患者在T3-5时点S100B、IL-6和TNF-a均低(P0.05或P0.01)。结论为预注高渗氯化钠羟乙基淀粉40注射液在肝肿瘤合并高血压患者硬膜外复合全身麻醉诱导期具有脑保护作用。 相似文献
42.
通过口腔疣状癌特殊类型发现与分型标准建立的探讨,阐明了口腔疣状癌分型的重要性以及对治疗的重要指导意义。并通过总结说明,任何一门学科的发展既依赖于科学技术的进步,也要求科学工作者有怀疑的精神,同时应具有一定的哲学思想,将哲学思想的各种理论贯穿研究其中。 相似文献
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为进一步检验相似语言标签的效应,采用经典的三角属性归纳范式,通过两个实验研究了"相似/相同"的真实语言标签对4岁幼儿归纳推理的影响.在实验一中,三角范式中的三个刺激物属于同一类别,在实验二中,三个刺激物属于两种不同的类别.每个实验均有三种条件:在控制条件中,实验者用"这个"指代每个客体;在相似语言标签条件中,靶刺激与知觉不相似的比较刺激具有相同的、且暗示了类别成员关系的词素(例如,翠鸟—飞机—鸵鸟);在相同语言标签条件中,靶刺激和知觉不相似的比较刺激共享相同的语言标签(例如,鸟—飞机—鸟).结果一致显示,与控制条件相比,幼儿在相似语言标签条件下表现出了更多的基于概念的归纳,表明在真实语言标签条件下也存在相似语言标签效应.同时,研究结果也显示,幼儿在相似和相同语言标签条件下的归纳没有显著差异,说明语言标签在幼儿归纳中更可能传递了概念信息,从而挑战了Sloutsky等的理论. 相似文献
45.
Jessica Carter 《Synthese》2008,163(2):119-131
This paper compares the statement ‘Mathematics is the study of structure’ with the actual practice of mathematics. We present
two examples from contemporary mathematical practice where the notion of structure plays different roles. In the first case
a structure is defined over a certain set. It is argued firstly that this set may not be regarded as a structure and secondly that what is important
to mathematical practice is the relation that exists between the structure and the set. In the second case, from algebraic
topology, one point is that an object can be a place in different structures. Which structure one chooses to place the object
in depends on what one wishes to do with it. Overall the paper argues that mathematics certainly deals with structures, but
that structures may not be all there is to mathematics.
I wish to thank Colin McLarty as well as the anonymous referees for helpful comments on earlier versions of this paper. 相似文献
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Three studies addressed children's arithmetic. First, 50 3- to 5-year-olds judged physical demonstrations of addition, subtraction and inversion, with and without number words. Second, 20 3- to 4-year-olds made equivalence judgments of additions and subtractions. Third, 60 4- to 6-year-olds solved addition, subtraction and inversion problems that varied according to the inclusion of concrete referents and number words. The results indicate that number words play a different role in conceptual and procedural development. Children have strong addition and subtraction concepts before they can translate the physical effects of these operations into number words. However, using number words does not detract from their calculation procedures. Moreover, consistent with iterative relations between conceptual and procedural development, the results suggest that inversion acquisition depends on children's calculation procedures and that inversion understanding influences these procedures. 相似文献
48.
How do people apprehend large numerosities? 总被引:1,自引:0,他引:1
People discriminate remarkably well among large numerosities. These discriminations, however, need not entail numerical representation of the quantities being compared. This research evaluated the role of both non-numerical and numerical information in adult judgments of relative numerosity for large-numerosity spatial arrays. Results of Experiment 1 indicated that judgments of relative numerosity were affected by the amount of open space in the arrays being compared. Further, the accuracy of verbal estimates of the numerosities of the arrays made upon completion of the comparison task bore little relation to performance on that task. Experiment 2, however, showed that numerical estimates for individually presented arrays were affected in much the same way by open space within or around the edges of the array as were the comparative judgments examined in Experiment 1. The findings suggest that adults heuristically utilize non-numerical cues as well as numerical information in apprehending large numerosities. 相似文献
49.
Adolescents develop a mature view on themselves: they view positive as well as negative self-attributes, but they hold a positive stance toward themselves. The literatures on identity, the self, parent-offspring relationships, and friendships provide hints on how such a view may develop. This article integrates this literature into an emotion-based dynamic systems mathematical model built to explain the development of maturity of such views. An innovative methodological design was used to collect empirical data: four students daily reported their experiences and emotions for a period of 5 months, while they temporarily studied abroad. At the beginning and end of this period, they were interviewed on their views on themselves. These mostly qualitative data were used to provide support to the suggested mathematical model. The usefulness, weaknesses, and strengths of such a methodological design and mathematical modeling are discussed. 相似文献
50.
This study examined whether children with mathematical difficulties (MDs) or comorbid mathematical and reading difficulties have a working memory deficit and whether the hypothesized working memory deficit includes the whole working memory system or only specific components. In the study, 31 10-year-olds with MDs and 37 10-year-olds with both mathematical and reading difficulties were compared with 47 age-matched and 50 younger controls (9-year-olds) on a number of working memory tasks. Compared with the age-matched controls, both groups of children with MDs performed worse on tasks tapping the central executive (e.g., visual matrix span) and the phonological loop (e.g., word span). More important, the MD group performed worse than the younger controls on the counting span task, whereas the group with comorbid mathematical and reading difficulties performed worse on the counting span task and the visual matrix span task. These findings provide support for the assumption that children with MDs have a working memory deficit. More specifically, children with MDs have a central executive deficit connected to concurrent processing and storage of numerical and visual information. 相似文献